Field of the Invention
The present invention relates to a liquid container and a detection apparatus for a liquid residue stored in the liquid container.
Description of the Related Art
In an apparatus in which liquid (or ink) supplied from a liquid container (or an ink tank) is continually consumed, like an inkjet printing apparatus, it may be desirable that a state in which a liquid residue in the liquid container is small be detected and notified to a user. As a configuration of detecting the liquid residue, there are provided a displacement member which is arranged within the liquid container and makes displacement along with liquid consumption and an optical sensor which detects light transmitted through the liquid container. According to such a configuration, the displacement member is adjusted such that, for example, in a case where the liquid residue within the liquid container is sufficient, it is placed at a position of shielding transmitted light of the optical sensor, and, in a case where the liquid residue within the liquid container is small, it is placed at a position of not shielding the transmitted light of the optical sensor. Then, depending on whether or not the optical sensor has detected the transmitted light, it is possible to determine whether the amount of liquid residue becomes smaller than a predetermined amount.
According to the configuration of residue detection as described above, the displacement member is required to be smoothly displaced along with liquid consumption, and placed at a position adapted to the amount of liquid residue. For example, Japanese Patent No. 4474960 discloses a configuration comprising a convex portion on a displacement member at a position facing an inner wall of a detection window in which an optical sensor detects transmitted light. Providing the convex portion ensures, even if a top end of the convex portion comes closest to an inner wall face, a sufficient distance between an area of a light shielding part other than the convex portion and the detection window, whereby surface tension of the ink interposed therebetween is suppressed to influence displacement of the light shielding part.